Explicitly calling the constructor

Hello !

I have a simple but interesting problem. I am using the 'malloc' routine to
reserve memory for a class object, and then trying to call the object's
constructor via the pointer returned. For some reason, this does not work at
all, and I have no idea why.

The reason why I need to do this is that I'm developing a COM component, and
in there it's suggested to use CoTaskMemAlloc to reserve memory instead of
the 'new keyword'. The object I'm trying to initialize is a complex class,
thus I need to call it's constructor.

Here is a code sample, to which Visual Studio .NET 2003 answers with error
C2273:

#include <stdlib.h>
#include <malloc.h>
#include <queue>
class CTestClass
{
public:
CTestClass()
{
m_nData = 0;
}
private:
int m_nData;
};

int main(void)
{
CTestClass* pData = (CTestClass*) malloc( sizeof(CTestClass) );

if ( pData )
{
pData->CTestClass();
free( pData );
}

return 0;
}


.

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